libs/ardour/butler.cc

   1 /*
   2     Copyright (C) 1999-2009 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23 #include <poll.h>
  24 #include "pbd/error.h"
  25 #include "pbd/pthread_utils.h"
  26 #include "ardour/butler.h"
  27 #include "ardour/io.h"
  28 #include "ardour/midi_diskstream.h"
  29 #include "ardour/session.h"
  30 #include "ardour/track.h"
  31 #include "ardour/auditioner.h"
  32
  33 #include "i18n.h"
  34
  35 using namespace PBD;
  36
  37 namespace ARDOUR {
  38
  39 Butler::Butler(Session& s)
  40         : SessionHandleRef (s)
  41         , thread(0)
  42         , audio_dstream_capture_buffer_size(0)
  43         , audio_dstream_playback_buffer_size(0)
  44         , midi_dstream_buffer_size(0)
  45         , pool_trash(16)
  46 {
  47         g_atomic_int_set(&should_do_transport_work, 0);
  48         SessionEvent::pool->set_trash (&pool_trash);
  49
  50         Config->ParameterChanged.connect_same_thread (*this, boost::bind (&Butler::config_changed, this, _1));
  51 }
  52
  53 Butler::~Butler()
  54 {
  55         terminate_thread ();
  56 }
  57
  58 void
  59 Butler::config_changed (std::string p)
  60 {
  61         if (p == "playback-buffer-seconds") {
  62                 /* size is in Samples, not bytes */
  63                 audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * _session.frame_rate());
  64                 _session.adjust_playback_buffering ();
  65         } else if (p == "capture-buffer-seconds") {
  66                 audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * _session.frame_rate());
  67                 _session.adjust_capture_buffering ();
  68         }
  69 }
  70
  71 int
  72 Butler::setup_request_pipe ()
  73 {
  74         if (pipe (request_pipe)) {
  75                 error << string_compose(_("Cannot create transport request signal pipe (%1)"),
  76                                 strerror (errno)) << endmsg;
  77                 return -1;
  78         }
  79
  80         if (fcntl (request_pipe[0], F_SETFL, O_NONBLOCK)) {
  81                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
  82                                 strerror (errno)) << endmsg;
  83                 return -1;
  84         }
  85
  86         if (fcntl (request_pipe[1], F_SETFL, O_NONBLOCK)) {
  87                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
  88                                 strerror (errno)) << endmsg;
  89                 return -1;
  90         }
  91         return 0;
  92 }
  93
  94 int
  95 Butler::start_thread()
  96 {
  97         const float rate = (float)_session.frame_rate();
  98
  99         /* size is in Samples, not bytes */
 100         audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * rate);
 101         audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * rate);
 102
 103         /* size is in bytes
 104          * XXX: Jack needs to tell us the MIDI buffer size
 105          * (i.e. how many MIDI bytes we might see in a cycle)
 106          */
 107         midi_dstream_buffer_size = (uint32_t) floor (Config->get_midi_track_buffer_seconds() * rate);
 108
 109         MidiDiskstream::set_readahead_frames ((framecnt_t) (Config->get_midi_readahead() * rate));
 110
 111         should_run = false;
 112
 113         if (setup_request_pipe() != 0) return -1;
 114
 115         if (pthread_create_and_store ("disk butler", &thread, _thread_work, this)) {
 116                 error << _("Session: could not create butler thread") << endmsg;
 117                 return -1;
 118         }
 119
 120         //pthread_detach (thread);
 121
 122         return 0;
 123 }
 124
 125 void
 126 Butler::terminate_thread ()
 127 {
 128         if (thread) {
 129                 void* status;
 130                 const char c = Request::Quit;
 131                 (void) ::write (request_pipe[1], &c, 1);
 132                 pthread_join (thread, &status);
 133         }
 134 }
 135
 136 void *
 137 Butler::_thread_work (void* arg)
 138 {
 139         SessionEvent::create_per_thread_pool ("butler events", 4096);
 140         pthread_set_name (X_("butler"));
 141         return ((Butler *) arg)->thread_work ();
 142 }
 143
 144 void *
 145 Butler::thread_work ()
 146 {
 147         uint32_t err = 0;
 148
 149         struct pollfd pfd[1];
 150         bool disk_work_outstanding = false;
 151         RouteList::iterator i;
 152
 153         while (true) {
 154                 pfd[0].fd = request_pipe[0];
 155                 pfd[0].events = POLLIN|POLLERR|POLLHUP;
 156
 157                 if (poll (pfd, 1, (disk_work_outstanding ? 0 : -1)) < 0) {
 158
 159                         if (errno == EINTR) {
 160                                 continue;
 161                         }
 162
 163                         error << string_compose (_("poll on butler request pipe failed (%1)"),
 164                                           strerror (errno))
 165                               << endmsg;
 166                         break;
 167                 }
 168
 169                 if (pfd[0].revents & ~POLLIN) {
 170                         error << string_compose (_("Error on butler thread request pipe: fd=%1 err=%2"), pfd[0].fd, pfd[0].revents) << endmsg;
 171                         break;
 172                 }
 173
 174                 if (pfd[0].revents & POLLIN) {
 175
 176                         char req;
 177
 178                         /* empty the pipe of all current requests */
 179
 180                         while (1) {
 181                                 size_t nread = ::read (request_pipe[0], &req, sizeof (req));
 182                                 if (nread == 1) {
 183
 184                                         switch ((Request::Type) req) {
 185
 186                                         case Request::Run:
 187                                                 should_run = true;
 188                                                 break;
 189
 190                                         case Request::Pause:
 191                                                 should_run = false;
 192                                                 break;
 193
 194                                         case Request::Quit:
 195                                                 pthread_exit_pbd (0);
 196                                                 /*NOTREACHED*/
 197                                                 break;
 198
 199                                         default:
 200                                                 break;
 201                                         }
 202
 203                                 } else if (nread == 0) {
 204                                         break;
 205                                 } else if (errno == EAGAIN) {
 206                                         break;
 207                                 } else {
 208                                         fatal << _("Error reading from butler request pipe") << endmsg;
 209                                         /*NOTREACHED*/
 210                                 }
 211                         }
 212                 }
 213
 214
 215 restart:
 216                 disk_work_outstanding = false;
 217
 218                 if (transport_work_requested()) {
 219                         _session.butler_transport_work ();
 220                 }
 221
 222                 boost::shared_ptr<RouteList> rl = _session.get_routes();
 223
 224                 RouteList rl_with_auditioner = *rl;
 225                 rl_with_auditioner.push_back (_session.the_auditioner());
 226
 227 //              for (i = dsl->begin(); i != dsl->end(); ++i) {
 228 //                      cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 229 //              }
 230
 231                 for (i = rl_with_auditioner.begin(); !transport_work_requested() && should_run && i != rl_with_auditioner.end(); ++i) {
 232
 233                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 234
 235                         if (!tr) {
 236                                 continue;
 237                         }
 238
 239                         boost::shared_ptr<IO> io = tr->input ();
 240
 241                         if (io && !io->active()) {
 242                                 /* don't read inactive tracks */
 243                                 continue;
 244                         }
 245
 246                         switch (tr->do_refill ()) {
 247                         case 0:
 248                                 break;
 249
 250                         case 1:
 251                                 disk_work_outstanding = true;
 252                                 break;
 253
 254                         default:
 255                                 error << string_compose(_("Butler read ahead failure on dstream %1"), (*i)->name()) << endmsg;
 256                                 break;
 257                         }
 258
 259                 }
 260
 261                 if (i != rl_with_auditioner.begin() && i != rl_with_auditioner.end()) {
 262                         /* we didn't get to all the streams */
 263                         disk_work_outstanding = true;
 264                 }
 265
 266                 if (!err && transport_work_requested()) {
 267                         goto restart;
 268                 }
 269
 270                 for (i = rl->begin(); !transport_work_requested() && should_run && i != rl->end(); ++i) {
 271                         // cerr << "write behind for " << (*i)->name () << endl;
 272
 273                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 274
 275                         if (!tr) {
 276                                 continue;
 277                         }
 278
 279                         /* note that we still try to flush diskstreams attached to inactive routes
 280                          */
 281
 282                         switch (tr->do_flush (ButlerContext)) {
 283                         case 0:
 284                                 break;
 285
 286                         case 1:
 287                                 disk_work_outstanding = true;
 288                                 break;
 289
 290                         default:
 291                                 err++;
 292                                 error << string_compose(_("Butler write-behind failure on dstream %1"), (*i)->name()) << endmsg;
 293                                 /* don't break - try to flush all streams in case they
 294                                    are split across disks.
 295                                 */
 296                         }
 297                 }
 298
 299                 if (err && _session.actively_recording()) {
 300                         /* stop the transport and try to catch as much possible
 301                            captured state as we can.
 302                         */
 303                         _session.request_stop ();
 304                 }
 305
 306                 if (i != rl->begin() && i != rl->end()) {
 307                         /* we didn't get to all the streams */
 308                         disk_work_outstanding = true;
 309                 }
 310
 311                 if (!err && transport_work_requested()) {
 312                         goto restart;
 313                 }
 314
 315                 if (!disk_work_outstanding) {
 316                         _session.refresh_disk_space ();
 317                 }
 318
 319
 320                 {
 321                         Glib::Threads::Mutex::Lock lm (request_lock);
 322
 323                         if (should_run && (disk_work_outstanding || transport_work_requested())) {
 324 //                              for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 325 //                                      cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 326 //                              }
 327
 328                                 goto restart;
 329                         }
 330
 331                         paused.signal();
 332                 }
 333
 334                 empty_pool_trash ();
 335         }
 336
 337         pthread_exit_pbd (0);
 338         /*NOTREACHED*/
 339         return (0);
 340 }
 341
 342 void
 343 Butler::schedule_transport_work ()
 344 {
 345         g_atomic_int_inc (&should_do_transport_work);
 346         summon ();
 347 }
 348
 349 void
 350 Butler::summon ()
 351 {
 352         char c = Request::Run;
 353         (void) ::write (request_pipe[1], &c, 1);
 354 }
 355
 356 void
 357 Butler::stop ()
 358 {
 359         Glib::Threads::Mutex::Lock lm (request_lock);
 360         char c = Request::Pause;
 361         (void) ::write (request_pipe[1], &c, 1);
 362         paused.wait(request_lock);
 363 }
 364
 365 void
 366 Butler::wait_until_finished ()
 367 {
 368         Glib::Threads::Mutex::Lock lm (request_lock);
 369         char c = Request::Pause;
 370         (void) ::write (request_pipe[1], &c, 1);
 371         paused.wait(request_lock);
 372 }
 373
 374 bool
 375 Butler::transport_work_requested () const
 376 {
 377         return g_atomic_int_get(&should_do_transport_work);
 378 }
 379
 380 void
 381 Butler::empty_pool_trash ()
 382 {
 383         /* look in the trash, deleting empty pools until we come to one that is not empty */
 384
 385         RingBuffer<CrossThreadPool*>::rw_vector vec;
 386         pool_trash.get_read_vector (&vec);
 387
 388         guint deleted = 0;
 389
 390         for (int i = 0; i < 2; ++i) {
 391                 for (guint j = 0; j < vec.len[i]; ++j) {
 392                         if (vec.buf[i][j]->empty()) {
 393                                 delete vec.buf[i][j];
 394                                 ++deleted;
 395                         } else {
 396                                 /* found a non-empty pool, so stop deleting */
 397                                 if (deleted) {
 398                                         pool_trash.increment_read_idx (deleted);
 399                                 }
 400                                 return;
 401                         }
 402                 }
 403         }
 404
 405         if (deleted) {
 406                 pool_trash.increment_read_idx (deleted);
 407         }
 408 }
 409
 410 void
 411 Butler::drop_references ()
 412 {
 413         SessionEvent::pool->set_trash (0);
 414 }
 415
 416
 417 } // namespace ARDOUR
 418